michael@0: // Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
michael@0: // Use of this source code is governed by a BSD-style license that can be
michael@0: // found in the LICENSE file.
michael@0: 
michael@0: #include "base/waitable_event_watcher.h"
michael@0: 
michael@0: #include "base/compiler_specific.h"
michael@0: #include "base/object_watcher.h"
michael@0: #include "base/waitable_event.h"
michael@0: 
michael@0: namespace base {
michael@0: 
michael@0: WaitableEventWatcher::ObjectWatcherHelper::ObjectWatcherHelper(
michael@0:     WaitableEventWatcher* watcher)
michael@0:     : watcher_(watcher) {
michael@0: };
michael@0: 
michael@0: void WaitableEventWatcher::ObjectWatcherHelper::OnObjectSignaled(HANDLE h) {
michael@0:   watcher_->OnObjectSignaled();
michael@0: }
michael@0: 
michael@0: 
michael@0: WaitableEventWatcher::WaitableEventWatcher()
michael@0:     : event_(NULL),
michael@0:       ALLOW_THIS_IN_INITIALIZER_LIST(helper_(this)),
michael@0:       delegate_(NULL) {
michael@0: }
michael@0: 
michael@0: WaitableEventWatcher::~WaitableEventWatcher() {
michael@0: }
michael@0: 
michael@0: bool WaitableEventWatcher::StartWatching(WaitableEvent* event,
michael@0:                                          Delegate* delegate) {
michael@0:   delegate_ = delegate;
michael@0:   event_ = event;
michael@0: 
michael@0:   return watcher_.StartWatching(event->handle(), &helper_);
michael@0: }
michael@0: 
michael@0: void WaitableEventWatcher::StopWatching() {
michael@0:   delegate_ = NULL;
michael@0:   event_ = NULL;
michael@0:   watcher_.StopWatching();
michael@0: }
michael@0: 
michael@0: WaitableEvent* WaitableEventWatcher::GetWatchedEvent() {
michael@0:   return event_;
michael@0: }
michael@0: 
michael@0: void WaitableEventWatcher::OnObjectSignaled() {
michael@0:   WaitableEvent* event = event_;
michael@0:   Delegate* delegate = delegate_;
michael@0:   event_ = NULL;
michael@0:   delegate_ = NULL;
michael@0:   DCHECK(event);
michael@0: 
michael@0:   delegate->OnWaitableEventSignaled(event);
michael@0: }
michael@0: 
michael@0: }  // namespace base